A new lizard (Squamata) was the last meal of Compsognathus (Theropoda: Dinosauria) and is a holotype in a holotype

A lizard preserved in the abdominal cavity of the Compsognathus longipes holotype traditionally has been referred to Bavarisaurus macrodactylus Hoffstetter. New observations on that specimen reveal that it differs from B. macrodactylus in the shape of the frontoparietal suture, the presence of paired parietals and the orientation of the parietal supratemporal processes. Phylogenetic analysis of 220 saurians and 839 morphological characters demonstrate the paraphyly of Ardeosaurus as traditionally used and the distinctiveness of three major squamate radiations in the Solnhofen Formation, and suggests rhynchocephalian affinities for the early lepidosaur Bharatagama rebbanensis. The gut content specimen is a diagnostic new species - a squamate holotype in a dinosaur holotype. It is an ardeosaurid based on the presence of a posteroventral process of the jugal, absence of a lateral parietal flange at the frontoparietal suture and a posteriorly broadened mandibular retroarticular process.